Federal agents arrested and charged four more people on Tuesday for their roles in the alleged sex cult NXIVM, according to the Albany Times Union.

In addition to the high-profile indictments of NXIVM’s founder Keith Raniere and former "Smallville" actress Allison Mack (pictured above) in April, charges have now been brought against the group’s co-founder Nancy Salzman, her daughter Lauren, and Kathy Russell, the group's longtime bookkeeper, the Times Union reported.

NXIVM’s operations director, Clare Bronfman, was arrested and charged on Tuesday as well. Bronfman is also the heir to part of the Seagram’s liquor empire.

The charges were part of a superseding indictment that was unsealed on Tuesday and obtained by the Times Union.

The indictment charges the six arrested with extortion, forced labor, sex trafficking, wire fraud, obstruction of justice, identity theft and harboring of aliens for financial gain.

It also alleges the parties used "harassment, coercion and abusive litigation to intimidate and attack perceived enemies and critics of Raniere," the Times Union reported.

NXIVM is described in the indictment as a “pyramid-structured organization” and the unsealing of the indictment is a massive development in the case against Raniere’s organization.

The shadowy group, which billed itself as a self-help organization, came into the public eye after a series of investigations led to the arrests of Raniere and Mack for allegedly coercing women into joining the secret group as "slaves" who were expected to have sex with Raniere, a "master."

It is alleged the women who joined were branded with the Raniere’s initials and were forced to sexually pleasure him and perform free labor, Oxygen.com reported.

Russell and the Salzmans will next appear in a federal court in Albany, N.Y., on Tuesday. Bronfman, who was arrested in New York City, will appear in a Brooklyn courthouse Tuesday afternoon, the Times Union reported.

Mack was release on $5 million bond, and Raniere is being held without bail.